#include "flash_eeprom.h"
#include "intrins.h"

/*Declare SFR associated with the IAP */
sfr IAP_DATA    =   0xE2;           //Flash data register
sfr IAP_ADDRH   =   0xE3;           //Flash address HIGH
sfr IAP_ADDRL   =   0xE4;           //Flash address LOW
sfr IAP_CMD     =   0xE5;           //Flash command register
sfr IAP_TRIG    =   0xE6;           //Flash command trigger
sfr IAP_CONTR   =   0xE7;           //Flash control register

/*Define ISP/IAP/EEPROM command*/
#define CMD_IDLE    0               //Stand-By
#define CMD_READ    1               //Byte-Read
#define CMD_PROGRAM 2               //Byte-Program
#define CMD_ERASE   3               //Sector-Erase

/*Define ISP/IAP/EEPROM operation const for IAP_CONTR*/
//#define ENABLE_IAP 0x80           //if SYSCLK<40MHz
#define ENABLE_IAP 0x81           //if SYSCLK<20MHz
//#define ENABLE_IAP 0x82            //if SYSCLK<10MHz
//#define ENABLE_IAP 0x83           //if SYSCLK<5MHz



//void Delay(unsigned char n);
void IapIdle();
unsigned char IapReadByte(unsigned int addr);
void IapProgramByte(unsigned int addr, unsigned char dat);
void IapEraseSector(unsigned int addr);

///*----------------------------
//Software delay function
//----------------------------*/
//void Delay(unsigned char n)
//{
//    unsigned int x;

//    while (n--)
//    {
//        x = 0;
//        while (++x);
//    }
//}

/*----------------------------
Disable ISP/IAP/EEPROM function
Make MCU in a safe state
----------------------------*/
void IapIdle()
{
    IAP_CONTR = 0;                  //Close IAP function
    IAP_CMD = 0;                    //Clear command to standby
    IAP_TRIG = 0;                   //Clear trigger register
    IAP_ADDRH = 0x80;               //Data ptr point to non-EEPROM area
    IAP_ADDRL = 0;                  //Clear IAP address to prevent misuse
}

/*----------------------------
Read one byte from ISP/IAP/EEPROM area
Input: addr (ISP/IAP/EEPROM address)
Output:Flash data
----------------------------*/
unsigned char IapReadByte(unsigned int addr)
{
    unsigned char dat;                       //Data buffer

    IAP_CONTR = ENABLE_IAP;         //Open IAP function, and set wait time
    IAP_CMD = CMD_READ;             //Set ISP/IAP/EEPROM READ command
    IAP_ADDRL = addr;               //Set ISP/IAP/EEPROM address low
    IAP_ADDRH = addr >> 8;          //Set ISP/IAP/EEPROM address high
    IAP_TRIG = 0x46;                //Send trigger command1 (0x46)
    IAP_TRIG = 0xb9;                //Send trigger command2 (0xb9)
    _nop_();                        //MCU will hold here until ISP/IAP/EEPROM operation complete
    dat = IAP_DATA;                 //Read ISP/IAP/EEPROM data
    IapIdle();                      //Close ISP/IAP/EEPROM function

    return dat;                     //Return Flash data
}

/*----------------------------
Program one byte to ISP/IAP/EEPROM area
Input: addr (ISP/IAP/EEPROM address)
       dat (ISP/IAP/EEPROM data)
Output:-
----------------------------*/
void IapProgramByte(unsigned int addr, unsigned char dat)
{
    IAP_CONTR = ENABLE_IAP;         //Open IAP function, and set wait time
    IAP_CMD = CMD_PROGRAM;          //Set ISP/IAP/EEPROM PROGRAM command
    IAP_ADDRL = addr;               //Set ISP/IAP/EEPROM address low
    IAP_ADDRH = addr >> 8;          //Set ISP/IAP/EEPROM address high
    IAP_DATA = dat;                 //Write ISP/IAP/EEPROM data
    IAP_TRIG = 0x46;                //Send trigger command1 (0x46)
    IAP_TRIG = 0xb9;                //Send trigger command2 (0xb9)
    _nop_();                        //MCU will hold here until ISP/IAP/EEPROM operation complete
    IapIdle();
}

/*----------------------------
Erase one sector area
Input: addr (ISP/IAP/EEPROM address)
Output:-
----------------------------*/
void IapEraseSector(unsigned int addr)
{
    IAP_CONTR = ENABLE_IAP;         //Open IAP function, and set wait time
    IAP_CMD = CMD_ERASE;            //Set ISP/IAP/EEPROM ERASE command
    IAP_ADDRL = addr;               //Set ISP/IAP/EEPROM address low
    IAP_ADDRH = addr >> 8;          //Set ISP/IAP/EEPROM address high
    IAP_TRIG = 0x46;                //Send trigger command1 (0x46)
    IAP_TRIG = 0xb9;                //Send trigger command2 (0xb9)
    _nop_();                        //MCU will hold here until ISP/IAP/EEPROM operation complete
    IapIdle();
}

